Ka-31 helicopter is intended for long-range detection of air targets of a fixed-wing/helicopter type, including detection at low altitudes, and over-waters ships, their tracking and automatic transmission of their data to the command posts. The helicopter can considerably increase combat mission efficiency of Navy ships, Army aviation and tank detachments by providing them with timely information about the actions of the ships, fixed-wing aircraft and combat helicopters of the enemy.

Ka-31 helicopter is developed on the basis of Ka-27 ship-borne coaxial helicopter. Under the transport cabin floor there is a compartment housing the support-rotating mechanism of a 6-m span antenna. To prevent the interference in the antenna all-round rotation plane the nose landing gear legs are retracted rearward into the cowlings flight-wise and the main legs are retracted upward. In stowed position the antenna is kept against the fuselage bottom. The search and attack equipment of Ka-27 helicopter intended for fighting against sub-marines is dismounted. Instead, a radio-electronic suite is installed for radar target detection, targets identification and transmission of the over-water and air situation data to the ship-based and ground-based command posts. Ka-31 is based on the ships and on the ground.

The core of the on-board avionics suite is powerful solid-state radar. The radio-electronic package automatically controls the helicopter flight over the specified route in any weather and climatic conditions. When the radio-electronic package is on, the antenna is extended and the navigator has elected the operational mode, all further operations are performed automatically without operator interference. The navigator role is simply to control the systems operation and to duplicate target observation on the display screen.

Developed for AV-MF, following cancellation of proposed joint-service, tandem-rotor, multirole V-50 and its replacement by what became Ka-50, meeting Army requirement only. Ka-252TB prototype (also known as Izdelie D2B or Izdelie 502) first flew 28 July 1976, possibly with Ka-25 nose or original narrow Ka-27/Ka-32 nose. Production at Kumertau (KAPP) from 1984.

Entered service with Northern and Pacific Fleets 1985; photographed on board assault ship Ivan Rogov in Mediterranean 1987, thought to be Ka-27B and given NATO reporting name 'Helix-B'; identified as Ka-29 combat transport at Frunze (Khodinka) Air Show, Moscow, August 1989; Ka-31 radar picket version completed initial shipboard trials on aircraft carrier Admiral of the Fleet Kuznetsov (then Tbilisi) 1990.

CURRENT VERSIONS:

Ka-29TB ('Helix-B'): Armed derivative for day/night, VFR and IFR, transport and close support of seaborne assault troops; in-the-field conversion from one role to the other. Non-retractable landing gear and 50cm wider armoured flight deck. Reportedly used by Experimental Combat Group in Chechen War in 1996. No recent production known.

Ka-31 (formerly Ka-29RLD: radiolokatsyonnogo Dozora: radar picket helicopter): Development began 1980; first flown October 1987; two examples (031 and 032) tested on Admiral of the Fleet Kuznetsov; state testing completed in 1996; limited production launched (for Indian Navy) at Kumertau Aircraft Plant, Bashkiriya, 1999. Indian aircraft have 12-channel Kronshtadt GPS with Abris digital moving map and a 152x203mm AMLCD screen.

Basic airframe of Ka-27 with broader flight deck; E-801 or E-801M (export) Oko (eye) early warning radar system by Radio Engineering Institute, Nizhny Novgorod, includes large rotating radar antenna (area 6.0m2) that stows flat against underfuselage and deploys downward, turning through 90° into vertical plane before starting to rotate at 6 rpm; landing gear retracts upward to prevent interference, nosewheels into long fairings. Once system has been switched on, antenna extended and operation mode selected, data on air targets flying below helicopter’s altitude, and on water surface situation, are acquired, evaluated and transmitted automatically to command centre, requiring only two crew (pilot and navigator, latter monitoring - but not operating - the system) in helicopter. Kronshtadt Kabris GPS navigation and display system. Loiter speed 100 to 120km/h at up to 3,500m; loiter duration 2h 30 min. Maximum surveillance radius 100 to 150km for fighter-size targets, 250km for surface vessels; up to 20 targets tracked simultaneously. Antenna can be retracted manually or explosively jettisoned in the event of a forced landing.

Two large panniers starboard side of cabin, fore and aft of main landing gear on helicopter numbered 032 (forward panniers only on 031); starboard airstair-type cabin door, aft of flight deck, divided horizontally into upward- and downward-opening sections, with box fairing in place of window; hatch window deleted above starboard rear pannier; new TA-8Ka APU positioned ahove rear of engine bay fairing, with slot-type air intake at front of housing, displacing usual ESM and IR jamming pods, gives radar and antenna an independent power supply. Tyre size 620x180 on main wheels, 480x200 on nosewheels. Tailcone extended by fairing tor flight recorder; no armour, guu door, stores pylons or outriggers.

Ka-33: Utility transport. Civilianised version of Ka-29TB shipborne assault transport. Designation revealed tit Moscow Air Show in August 1997; no further details released and no known conversions.

CUSTOMERS: Total of 59 Ka-29s built for Russian Federation Naval Aviation (about 45) and Ukrainian Navy (about 12). Following 1996 evaluation, four Ka-31s ordered in August 1999 by Indian Navy for delivery in 2001 and basing aboard aircraft carriers and 'Krivak' class destroyers; further five ordered. February 2001. Additional 12 maybe required. Fust flight of Indian Ka-31 16 May 2001; by October 2001, first two Indian airframes delivered from KAPP to Kamov at Moscow for avionics installation; flight trials completed of first two Indian aircraft by September 2002; remaining seven scheduled to follow in 2003. In October 2002, Kamov reported a second export customer for Ka-31s in addition to Indian Navy.

COSTS: Indian Navy batch of four priced at Rs4 billion (US$92 million) (2000); second five cost US$108 million (2001).

POWER PLANT: Two Klimov TV3-117VMA turboshafts, each 1,633kW. Engines started by APU. Fuel tanks filled with reticulated polyurethane foam for fire suppression.